0000000000294342
AUTHOR
Quinten A. Akkerman
Effects of Oxygen Plasma on the Chemical, Light-Emitting, and Electrical-Transport Properties of Inorganic and Hybrid Lead Bromide Perovskite Nanocrystal Films
We show that oxygen plasma affects in different ways the structural, chemical, optical, and electrical properties of methylammonium and cesium lead bromide nanocrystals. Hybrid organic–inorganic nanocrystals were severely and quickly degraded by oxygen plasma at 50 W. Their photoluminescence was quenched with almost 100% loss of the initial quantum yield, which is linked to decomposition of the nanocrystals. Inorganic nanocrystals were more resistant to oxygen plasma in the same conditions. Despite a moderate loss of photoluminescence and electrical conductivity, oxygen plasma had a positive impact, removing unbound ligands and resulting in more ohmic behavior of the film. This paves the wa…
In situ transmission electron microscopy study of electron beam-induced transformations in colloidal cesium lead halide perovskite nanocrystals
An increasing number of studies have recently reported the rapid degradation of hybrid and all-inorganic lead halide perovskite nanocrystals under electron beam irradiation in the transmission electron microscope, with the formation of nanometer size, high contrast particles. The nature of these nanoparticles and the involved transformations in the perovskite nanocrystals are still a matter of debate. Herein, we have studied the effects of high energy (80/200 keV) electron irradiation on colloidal cesium lead bromide (CsPbBr3) nanocrystals with different shapes and sizes, especially 3 nm thick nanosheets, a morphology that facilitated the analysis of the various ongoing processes. Our resul…
Molecular Iodine for a General Synthesis of Binary and Ternary Inorganic and Hybrid Organic-inorganic Iodide Nanocrystals
We report the synthesis of various binary and ternary inorganic and hybrid organic–inorganic iodide nanocrystals (NCs) starting from molecular iodine (I2). The synthesis described herein utilizes a reaction between I2 and oleylamine, which results in oleylammonium iodide, an iodide precursor that can be directly used in the preparation of iodide-based NCs. The generality of the synthesis was demonstrated by synthesizing KI, RbI, CsI, AgI, CsPbI3, FAPbI3, Cs4PbI6, Cs3Bi2I9, FA3Bi2I9, and RbAg4I5 NCs. Furthermore, the syntheses are facile and are carried out in vials heated on a hot plate in air. They exhibit not only narrow size distributions, but also, in the case of lead-based perovskites …